Four-cycle explosive-vapor engine.



No. 706,733. Patented Aug. 12, I902.

G. ERIKSUN.

FOUR CYGLE EXPLUSIVE VAPOR ENGINE.

(App ication filed Oct. 9, 1901. (No Model.) r 2 Sheets-Sheet I.

WITNESES: V l I INYENTORI 01 50 en. a a '7 'ATTORNEY- V THE NORRIS #:Tzns co. PfiQTO-LITHQ, WASHINGTON. n. c.

No. 706,733. Patented Aug. l2, I902.

. G ERIKSON FDUB CYCLE EXPLUSIVE VAPOR ENGINE.

(Application filed 00b. 9, 1901.

(No Model.)

2 Sheets-Sh eet 2.

WITNESSES:

lNVENTOR BY v S E 7 ATTORNEY UNITED STAT PATENT OEEIGE.

GUSTAF ERIKSON, OF soDERTELJE, sWEDEN, ASSIGNOR TO VAGNFABRIKS AKTIEBOLAGET I soDEETELJE, OF soDERTELJE, SWEDEN.

I FOUR-CYCLE EXPLOSlVE-VAPOR ENGINE.

SPECIFICATION forming part of Letters Patent No. 706,733, dated August 12, 1902.

Application filedOctober 9, 1901. $eria1No. 78,029. (No model.)

To (l/ZZ whom it may concern:

Be it knownthatLGUsrAr ERIKSON, a subject of the King of Sweden and Norway, residing at sodertelje, in the Kingdom of Swe- 5 den, have invented certain Improvements in Internal-Combustion Engines, of which the following is a specification.

This invention relates to four-cycle internal-combustion engines or explosive-vapor 1o engines of the type provided with automatic admission-valves; and the object of the invention is to provide means for governing the power and rotary speed of an engine of this class or type. One defect found in engines of this type now in use is their inability to vary speed and torque within wide limits. For this reason it has not been found feasible in many instances to substitute internal-combustion engines for steam-engines or electric 2o motors. An instance of this kind is an engine for operating a machine-tool where a variable speed with a constant torque is required. Another instance is the employment of an engine for propelling a vehicle where it is necessary to introduce complicated gearing between the motor and the vehicle-wheels in order to control the speed of the vehicle.

The present engine, in which my invention is embodied, is capable of variation in velocity within wide limits as readily as a steam-en gine or electric motor, and, furthermore, it will adjust itself automatically to variations in load, so that when theload increases the torque is also increased in proportion to the increase in the load, the rotary velocity being,

however, proportionately reduced.

In the accompanying drawings, which serve to illustrate-an embodiment of the invention,

Figure l is a sectional side elevation of the engine, and Fig. 2 is a plan of the same. Fig.

3 is an enlarged sectional view of the dashpot device.

A is the cylinder of the engine, B the piston therein, and J the connecting-rodwhich couples the piston to the crank K on the main shaft Q. ing U.

P is the vapor-inlet to the ignition-chamber O,the admission being controlled by a valve D.

E is the exhaust-valve, I is its stem, and II its spring. This valve is opened at each This shaft has hearings in the caslimits. exhaust-valve are such as to permit the lato shaft R, driven by suitable gearing from the engine-shaft Q.

All of the above features are known in this class of engines and are employed herein to illustrate the application to such an engine of the present invention, which will now be described with especial reference to Figs. 1 and 3.

On the stem I of the exhaust-valve Eis secured a piston F, which plays in a fixed cylinder or pot G, forming a dash-pot device. The rod I plays snugly through an aperture in the closed end of the cylinder G, and there is an inlet or port L in the cylinder to admit air to the latter back of the piston through an aperture 0, Fig. 3, and to allow the incarcerated air to escape. Theport L is controlled by a screw-valve M. In the side of the cylinder G is an air-inlet port N, which is opened to the atmosphere when the piston is drawn out to a predetermined extent. The object of the dash-pot is to retard the closing of the exhaust-valve by its spring through the incarceration of air in the cylinder behind the piston, the time of escape of the air at the port L being regulable by the Valve M. The time required for the closing of the exhaust-valve depends on the strength of the closing-spring H of the valve and the resistance to the spring ofiered by the graduallyescaping incarcerated air behind the piston of the dash-pot. This resistance can obviously be varied by means of the valve M, thus making the closing period of the valve of longer or shorter duration at will within The means employed for opening the ter to close under normal conditions or without" a dash-pot when the engine is on the dead-center. The closing period of the exhaust-valve is intimately connected with the cycle of operations within the motor, since 5 the automatic admission-valve cannot open during the suction-stroke until the exhaustvalve is closed and a vacuum has been subsequently formed. Before the closing of the exhaust valve the waste gases are drawn back into the cylinder in quantity determined by the shorter or longer closing period of the exhaust-valve. The quantity of explosive mixture subsequently drawn in. is thus made dependent on the quantity of waste gases previously drawn back-that is, on the relation of the closing moment of the exhaustvalve to the beginning of the suction-stroke.

By using a device for controlling the closing period of the exhaust-valve it is possible, first, to vary the power of the engine while retaining a constant velocity; second, to vary the velocity of the engine under a constant load, and, third, to obtain automatic governing control of the power and velocity of the engine according to the variations in load.

Case 1. When the engine is running at a constant velocity and the resistance of the dash-pot is varied, the moment of closing the exhaust-valve will be varied, a greater or less quantity of waste gases will be drawn back, a smaller or greater quantity of explosive mixture drawn in, and as a result the violence of the explosions and the power of the engine will be varied.

Case 2. With a constant load if the resistance oifered by the dash-pot be decreased the exhaust-valve will close earlier on the suctionstroke, a smaller quantiy of waste gases will be drawn back, a larger quantity of explosive mixture will be drawn in, the violence of the explosions will increase, and the velocity of the engine will be correspondingly increased. In consequence of the increased speed of the engine, however, the closing of the exhaustvalve on the suction-stroke will soon be restored to the original moment in relation to the suction-stroke and a condition of continuance will be maintained. When the resistance offered by the dash-pot is increased,a diminished velocity will result.

Case 3. If the load increases while the resistance offered by dash-pot is constant or permanently adjusted, the velocity of the engine will decrease and the moment of closing of the exhaust-valve will occur earlier on the suction-stroke. As a result a smaller quantity of Waste gases will be drawn back, a larger quantity of explosive mixture will be drawn in,and the explosions will increase in violence. This will continue until the closingof theexhaust-valve on the suction-stroke shall occur at such a time as to barely admit of a quantity of explosive mixture being drawn in sufficient for the increased velocity, a condition of continuance at a decreased velocity now beginning. The reverse action will take place when the load is decreased.

The passages L and O of the dash-pot are made large, so that when they are fully open the dash-pot will make no appreciable resistance and the exhaust-valve can close when the engine is at or near the dead-center.

I have shown a simple dash-pot device for effecting the object soughtnamely, to more or less weaken the explosive mixture, so as 'to modify the force of the explosion; but I do not limit myself to this particular means for effecting the above object, as other equivalent means may be employed as well. The dash-pot device may be located and operated in any manner, so longasit accomplishes the object stated. As the admission-valve with this governing means always permits of completely filling the cylinder, the compression always remains constant. As a result the ignitionis alwaysinsured,even when thecharges are Weak, this not always being the case with the mode of governing by means of throttling. In governing by means of throttling the compression falls with the throttling. Consequently the ignition becomes uncertain when the charges are weak, and the eifect is lowered.

Having now described my invention, what I claim as new, and desire to obtain by Letters Patent, is

1. A four-cycle internal-combustion engine having a suction admission-valve for the explosive mixture, a valve communicating with the explosion-chamber and closing outward, automatic means for opening said valve at regular intervals, a spring for closing said valve, and dash-pot device for retarding the closing of the last-named valve after the beginning of the suction-stroke, substantially as set forth.

2. Afour-cycle internal-combustion engine having as an automatic means for controlling the sucking in of the explosive mixture, an exhaust-valve communicating with the explosion-chamber, means operated by the engine for opening said valve at regular intervals, a spring for closing said valve, and means for retarding the closing of said valve by its spring, said means comprising a fixed cylinder having an inlet for air and a valvecontrolled outlet for the same, and a piston in said cylinder and fixed on the stem of the last-named valve, substantially as set forth.

3. A four-cycle internal-combustion engine havinga suction admission-valve for the explosive mixture, an exhaust-valve, automatic means for opening said exhaust-valve at all times to the same extent, a spring which closes said valve, and means for retarding the exhaust-valve, said means comprising a fixed cylinder or pot G, having a lateral airinlet N and a valve-controlled outlet 0, a screw-valve M controlling said outlet, and a piston F, in said cylinder or pot and connected with the stem of the exhaust-valve.

In witness whereof I have hereunto signed my name in the presence of two subscribing witnesses.

GUSTAF ERIKSON.

Witnesses:

ERNST SVANQVIST, A. F. LUNDBORG.

ILO 

